Slide rules

The accuracy of the presented methods was verified using test pipes with various diameters and wall thickness of which the wall thickness was measured independently using a slide-rule. Both on film and on the monitor the wall thickness could be determined within an accuracy of ca. 0.2 - 0.3 mm. 

In the beginning, quantum chemists had pencils, paper, slide rules and log tables. It is amazing that so much could have been done by so few, with so little. 

Rechen-schieber, -stab, m. slide rule, -stift, m. slate pencil, -tafel, /. reckoning table multiplication table nomograph, nomogram slate blackboard counting board, -ver-fahren, n. method or process of calculation. 

Any computation, whether performed by a slide rule, computer workstation or brain, is inherently a physical process, and as such is subject to whatever laws and limitations apply to physical systems in general. It is a natural question to ask, then, whether there exists a fundamental thermodynamic limit to computation i.e. 

The advent of reasonably priced hand-held calculators has replaced the use of both logarithms and slide-rules for statistical calculations. In addition to the... 

This type of basic information has been reviewed for many centuries with different types of materials and more recently (in just over a century) with plastics. Recognize the design basics and/or fundamentals remain the same. Their interpretation and applicability improves with time. It is like saying 2 + 2 = 4 for the many past centuries. Now we can say it with a computer where in the recent past we used an abacus, adding machine, slide rule, etc. 

The Field of Numerical Analysis.—As used here, numerical analysis will be taken to represent the art and science of digital computation. The art is learned mainly by experience hence, this chapter will be concerned with explicit techniques and the mathematical principles that justify them. Digital computation is to be contrasted with analog computation, which is the use of slide rules, differential analyzers, model basins, and other devices in which such physical magnitudes as lengths, voltages, etc., represent the quantities under consideration. 

With liposome partitioning, however, the rule slips to diff 1-2. This means SIP partitioning starts at about pH 8.5 for weak bases whose pKa values are near 9.5 (e.g., Figs. 5.7b, 5.11). So, all who published anomalous values of log P em may need to get out their slide rules 1429—4-321 (What we know now was not known then.)... 

Plots of boiling points, hunts for data, corrections, slide rules, log paper, eraser dirt, pencil shavings, and all the rest of the paraphernalia that takes the place of tea leaves and crystal spheres in the life of the scientific clairvoyant, were brought into play, he joked. 

Whenever the same series of calculations is repeated a number of times, even with different sets of data, the use of a computer should be considered. For instance, the calculations of the net present value is very straightforward. It can easily be done using tables, a calculator, and/or a slide rule. However, it can also be done on a computer, and this would relieve the engineer of the responsibility of repeatedly performing the calculations. This will give him some time to analyze and compare the results. Besides this, he can also obtain from the same data the payout period and the return on the investment. He could even combine this with the program for the rate of return, and obtain all the major economic indicators for the same effort previously required to obtain any single one. 

Lawson, J.R., and Quintiere, J.G. 1985. Slide Rule Estimates of Fire Growth. National Bureau of Standards, NBSIR 85-3196, Washington (June 1985). 

Disposal Slide Rule. This is a handy, ready reference slide rule foe Explosive Ordnance... 

Radiological) agents which might be encountered in expl ordn incidents or accidents. The methods of disposal outlined in the slide rule are for the guidance of trained personnel and not intended for use by unskilled persons unfamiliar with the items or procedures covered Ref Lt. R.R. Vennell, "CBR Munitions and Reconnaissance and Disposal Slide Rule",... 

The Bragg and Lipson charts cannot be used for these expressions. The following method uses slide-rule technique and has been found to save much time and effort. A strip A is prepared (Fig. 164) on which phase angles and the corresponding cosine and sine values are marked. For a particular atom in the structure the postulated coordinates are marked on a separate strip of paper B. The phase angle for any crystal plane hkl is found by placing the two strips together, first of all with their... 

Beyond this initial theoretical drawing-board-and-slide-rule approach, of course, lies the critical need for experimental proof in actual process machinery and prototype field trials, which should be included as a 4th dimension in such a schematic diagram, and is the final pragmatic judgment to determine technical success of any plastic product. This is the direction in which applications research and product design must grow in the future, in order to convert plastics art into plastic science. 

With the birth of the electronic hand calculator and the death of the slide rule, the teaching of general chemistry entered a new era. Unfortunately, the calculator did not bring automatic understanding of chemistry analyzing and solving problems is just as difficult as ever. The need for detailed explanations, drill, and review problems is still with us. 

The above is an incomplete list, given to illustrate the level of preparation we are presuming in this text. If you find very much of this list partly or wholly unfamiliar, you don t have to give up, but have a good general chemistry textbook available for study and reference—and use it Some useful general chemistry books are listed at the end of the chapter. A four-place table of logarithms will be necessary a set of ball-and-stick models and a chemical handbook will be very helpful, as would be a small electronic calculator or slide rule to carry out the simple arithmetic required for many of the exercises. 

The second method is a similar procedure the cap of the product s container (plastic, glass or can) is punctured with a needle. Carbon dioxide is expelled from solution by vigorous shaking, and the headspace pressure is recorded. From the pressure rise, the volume of carbon dioxide dissolved in the product can be determined. This method is probably one of the most commonly used procedures for measuring carbonation however, the exact method used varies from one manufacturer to another. One supplier of this type of carbonation tester is Stevenson Reeves of Edinburgh, which also sells a slide rule to convert pressure rise measurements into carbonation levels. Information about their products can be found on their website (http //www.stevenson-reeves.co.uk). 

Considering the fact that these calculations were made on a slide rule and that relatively small differences of large numbers are involved, the agreement with the previous method is very good. 

The history of human mathematical computations goes back for several millenia. The need for numerical computations has increased since the age of enlightenment and the industrial revolution three centuries ago. For the last 50 years, the human race has become more and more dependent on numerical computations and digital computers. Computational techniques have developed from early hand computations, through table look up, mechanical adding and multiplying devices, the slide rule etc, to programmable electronic computers, mainframes, PCs, laptops, and notebooks. 

In nearly all practical chemical calculations, a precision of only two to four significant figures is required. Therefore the student need not perform multiplications and divisions manually. Even if an electronic calculator is not available, an inexpensive 10-in slide rule is accurate to three significant figures, and a table of 4-place logarithms is accurate to four significant figures. 

W. D. Williams, Some early chemical slide rules , Bull. Hist. Chem., 1992,12, 24-29. 

A long division in which most or all of the digits have been replaced by asterisks to form a cryptarithm. slide rule... 

The integrated expression is not easily solved for C hence, unlike the case of first-order kinetics, no attempt is made to write a general expression for the accumulated residues. Instead, the equation was solved numerically for a range of values for the constants, Vm and Km, using the Newton-Raphson method for numerical approximation. This was programmed for a computer easily, although log table and slide rule or calculator will do the same job but in more time. 

The method described above for calculating high temperature equilibria is straightforward and was selected to demonstrate the basic principles. There are, however, several techniques which reduce the number of numerical operations. Such procedures are of particular value when nitrogen is present (as N2 and NO) or if the fuel mixture is so rich that elemental carbon is deposited. The well-known Hottel charts (H5) contain the equilibrium compositions at many temperatures and pressures for the H + O + C + N system. An excellent approach to the slide-rule calculation of high temperature equilibria was developed by... 

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